


a den of blasphemy

by hydrangeamaiden



Series: Kurovan Anthology [3]
Category: Mogeko Castle, 廃れ夢 | Obsolete Dream
Genre: Creampie, Explicit Sexual Content, F/M, I'm not using the underage tag because they are both over a hundred years old and demons, Incest, Parent/Child Incest, Vaginal Fingering, blowjob
Language: English
Status: Completed
Published: 2018-05-12
Updated: 2018-06-05
Packaged: 2019-05-05 18:23:38
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 5
Words: 4,281
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14624418
Author URL: https://archiveofourown.org/users/hydrangeamaiden/pseuds/hydrangeamaiden
Summary: On their way home from a trip, Kurotsuno and Sullivan take a detour through Mogeko Castle.EDIT: fic will be bumped up to explicit rating for sexual content





	1. Chapter 1

The train doors opened to a familiar station, but not the one Kurotsuno wanted to see. Sullivan, now visibly nervous, kept close as they stepped onto the platform. Behind the chain-link fence, something rustled in the bushes and disappeared. Sullivan squeaked and put a hand on Kurotsuno’s shoulder. She could feel his hand trembling, and sighed a weary sigh.

“Aren’t you supposed to be the parent here? Grow up.” Kurotsuno scowled and brushed his hand away. Any sense of danger she should have had was absent; all the times she had been here, she was always with a friend or someone to protect her. Even as the peak of Mogeko Castle became visible over the tree line, she wasn’t scared.

Sullivan, on the other hand, was a lot more cautious—and rightfully so. While Kurotsuno practically skipped across the stone bridge, he lingered behind, holding both their luggage in each hand.

“The train wasn’t supposed to let us off here,” he protested as Kurotsuno pulled on the doorhandles. “Olivia, don’t go off by yourself! You’ll get lost again.”

But Kurotsuno knew better. Once you stopped at Mogeko Castle, there was only one way out: by going inside. It sounded contradictory, but it was true. She even hoped to ditch Sullivan while she was there, but he caught the door with his foot before she could shut it on him. He was now standing in the main hall with her, huffing and looking almost as frustrated as she was right now.

“I have my phone. I can just—huh?” Kurotsuno patted herself down and checks all her pockets, but they were all frighteningly empty. She looked at Sullivan with pure betrayal on her face as he held up her backpack. “Bastard.”

“Watch your language,” Sullivan scolded, holding her backpack out of reach when she tried to grab it. Kurotsuno saw a smug smile curving his lips and scowled; she knew exactly what he was playing at. Holding her phone hostage, what a little bitch. She decided to settle this with violence, but Sullivan had a counter for her knife, too: “If you stab me, the Mogekos will be smell my blood and, um.“

Kurotsuno lowered her weapon and squinted up at him. He had started to shake when she brought out a weapon, which was revenge enough in her book. 

“A-anyway, it’s, um, safer if we stay together,” he said as he handed her backpack over. As Kurotsuno stuck her arms through the straps, she realized she felt a little disappointed that he caved so easily. He was gonna lose her if he didn’t stand his ground. He’d get to hold her hand if he just took it instead of offering his own with an awkward smile.

“Let’s go?”

Kurotsuno just grunted and shoved her hands into her pockets.


	2. Chapter 2

**Notes for the Chapter:**

> I was going to save the smut for a later chapter, but as I was writing things kind of escalated, oops. Of the three chapters I have planned, two of them will have smut and the last one will have a full-blown sex scene. I figured it'd be easier to just write outright porn so I wouldn't be worrying about 'oh should I rate this fic mature or explicit'? It's much easier this way.

“Hey—don’t touch that!” Sullivan cried out for the thousandth time, but Kurotsuno remained as steadfast as ever in her quest to touch everything. If they were to go through the castle, she didn’t want to leave empty-handed. She had found her own way around Sullivan confiscating her phone: instead of straying from his side, she dragged him around with her.

However, the problem of traveling with someone was that they might not have too little or too much stamina. In Sullivan’s case, he had parked himself on the edge of one of the many beds in the room, refusing to move until he had rested up. He was helpless to keep Kurotsuno from going through the drawers in search of something interesting.

It was lucky that the Moffukos were so docile. Even as Sullivan took off his shoes and curled up atop the covers, they did not try to bother him. Perhaps it was their sickness, or the presence of another demon. Kurotsuno, waiting for the other shoe to drop, kept glaring around the room until Sullivan spoke up again.

“There’s a plug here. Why don’t you charge your phone and relax for a bit?” he suggested, gesturing to the wall next to the bed. Kurotsuno stalked over, expecting nothing and being surprised when she found that he was, in fact, telling the truth.

“There’s no need to be so nervous. If something happens, I’ll protect you.” Sullivan propped himself up on his elbow and held Kurotsuno’s backpack out to her. When she snatched it away with a glare, his smile faltered. No, it had softened. The longer Kurotsuno maintained eye contact, the more flustered she felt, until she gave up and looked away. It was unfair that he had to go and say things like that when she was trying her damndest to be angry at him. Pouting a little, she plugged in her phone and sat on the floor in front of it.

There was a long period of silence, during which Sullivan put a hand on her head and began to stroke her hair. The hairs on Kurotsuno’s arms stood on end, as they often did when she was touched unexpectedly. When his fingers trailed down her neck, however, she decided that she was fine with it. The way he brushed through her hair and caressed her skin was enough to distract her from her foul mood. She scooted closer until she was leaning against the bed, giving him enough reach to slide his hand down the back of her shirt.

Feeling unsatisfied with just this, she crawled onto the bed next to him and closed her eyes. It sometimes felt soothing when there was nothing to look at. If she were to make eye contact and see his tender gaze, she would erupt from embarrassment. She felt much more comfortable feeling and squirming as Sullivan’s hand went between her legs. He rubbed her bare thighs and the sensitive parts beneath her panties, until she was gasping.

Kurotsuno slid her hand across the comforter until she felt the bulge in Sullivan’s pants. Inexperienced as she was, she could only fumble with it while he traced circles around her clit. His other hand held the small of her back, and with his lips against hers, she found it impossible to be angry at him.

As usual, Sullivan would not leave her alone until she came on his hand with a soft gasp. She went slack against the bed, panting, and opened one eye to see Sullivan licking her juices off his fingers. Turning bright red, she slapped her hands over her face. She was going to need an extra ten minutes to recover from seeing that.


	3. Chapter 3

Not much time had passed since, according to their phones, but it felt like days had passed since they entered the castle. It was hard to tell which floor they were on; the best idea they had was that they were ‘high up’, and in some kind of hospital. If Kurotsuno had some kind of fellatio-related accident, at least they’d be able to get medical attention. She had inherited her squirminess from her father and had specifically instructed him to lie down while she went to work. In all honesty, the worst thing that could happen was Sullivan accidentally cock-slapping her in the face, but it was funnier to imagine otherwise (she would never admit this).

The girth and length of his cock left nothing to be desired, and was in fact too much for her to fit into her mouth. Curled comfortably atop his legs, she sucked at the head and then mouthed her way down the shaft. One arm was folded to keep his hips down, while her other hand massaged his balls. Sullivan had a hand over his mouth to stifle his moans. His hard-on hadn’t gone down since he fingered Kurotsuno, and was clearly enjoying this release—though he was trying not to show it. His reservation only egged Kurotsuno on. She did not want to owe him anything from the last time they touched each other.

Obligation was far from the only reason she dragged her tongue along his cock. When she tongued his urethra, the salty taste of precum stung her mouth. When she focused in on the spot, she felt his hand in her hair, gently easing her down. Gosh, he was needy. Kurotsuno could only get a little bit into her mouth. As she dipped her head, however, she felt Sullivan lift it back up.

“What?” she asked, voice hoarse. Sullivan sat up a little and pulled her forward by the shoulders.

“I want to put it in. Let me cum inside.” His voice came out as a desperate whine, and Kurotsuno had half the mind to indulge him. She sat up fully, straddling his waist and pushing him back down by the shoulders. The tip of his twitching cock brushed against her clothed crotch.

“We have to find a condom first,” Kurotsuno said, and practically saw the moment the spark left his eyes. He gulped and nodded when she added, “I don’t really want to walk around with cum inside of me, you know…”

There was a bigger worry: the possibility of illness, especially in a place like Mogeko Castle. Kurotsuno, instructing Sullivan to keep his hands off his penis, rolled off the bed and dug into her backpack. Nothing. After five minutes, Sullivan was searching through his suitcase too, with his dick flapping majestically against his thighs. Nothing. They did not pack a single condom. Kurotsuno sighed heavily, but figured they could compromise until they found contraceptives.

“Well, what do you want t—“ Sullivan was cut off when Kurotsuno put a hand over his mouth.

“I guess you can cum in my mouth.” She shrugged and unbuttoned her shirt while he got back up on the bed. Once he was seated, she pushed his knees apart. His dick, coated with precum and saliva, was juicy and twitching in her mouth. His legs spasmed when she wrapped her lips around the tip and sucked. Warm, thick cum flooded into her mouth. It quickly overflowed and dribbled down her chin, dripping onto her bare chest.

Kurotsuno drew back and spluttered, caught between swallowing and spitting it out. The sound of coughing made Sullivan’s dick go limp, and he leaned forward to help clean her up while apologizing profusely.

—

It was strange that Mogeko Castle, a place infamous for having wild, uninhibited sex, did not seem to have a single condom. Maybe it was because Mogeko Castle prided in having raw sex. Kurotsuno was too frustrated to care about the specifics, and her anger only rose when they scoured the entire floor only to find nothing. 

A couple of Mogekos chittered when she stomped by, and despite her increasing anxiety, she noted that they were the first ones she had seen all day. Strange. Kurotsuno kicked one away from her leg and kept walking.

“Olivia, wait up.” Kurotsuno stopped at the end of the hallway, and looked over her shoulder. Sullivan was lagging behind, panting and dragging his suitcase behind him. At the sight of her scowl, he shrank away a little and let her open the door. The smell of dust permeated the air, and the lights flickered when Kurotsuno flipped the switch.

They had stepped into a room covered wall to wall with file cabinets. At the back was a desk with a metal folding chair and an old computer. The papers in front of it wavered in the breeze of a draft coming from the ceiling. Unlike the rest of the castle, this place felt sterile and cold.

Kurotsuno could already tell that this was going to be just paperwork, but Mogeko Castle was full of surprises. There might be a condom in here. She folded her sleeves to her elbows and set to work.

The first drawer she checked was full of sex toys: a massive dildo, a string of anal beads, cock rings, and various others that she didn’t even know the functions of. In fact, it looked like some of them were made for aliens. Both she and Sullivan stared.

“Absolutely not. You don’t know where those have been,” Sullivan declared, shutting the drawer. Kurotsuno scowled, but only because she didn’t want to admit he had a point.

The second drawer had a lot of folders, like what would be in an actual office. Upon further inspection, they were all empty. Kurotsuno checked between them just to be sure, though. No dice. She was starting to get mad again.

The third drawer, for some reason, had several unopened bottles of pineapple juice. As Kurotsuno reflected on how thirsty she was, she heard Sullivan sigh and go ‘Of course’. She then remembered something she had read online, pushed one of the bottles against his face.

“Olivia! You don’t know what’s in that!” Sullivan protested.

“Sure I do. The ingredients are right here.” Kurotsuno pointed to the label on the bottle. “Pineapple juice, high fructose corn syrup, I can’t pronounce these ones…”

While she was distracted, Sullivan took the bottle from her and put it back. “I’ll get a bottle of water for you from the vending machine later, okay?”

Kurotsuno grunted and went to the next drawer. At first glance, she wasn’t surprised to see it was full of cards. The Mogekos could be so childish that card games weren’t beyond them. Then she picked one up and looked into the face of a gently-smiling human girl.

Kikutake Naru, Class 1-B.

Kurotsuno blinked and picked up another. Kamioka Mitsu, Class 2-A. Muro Sayuri, Class 1-C. Ichisada Maya, Class 3-B. Nagatsuka Eri. Ichiro Miyo. Kurai Yonaka. Asahi Takako. Olivia.

Her stomach twisted in a way that made her think she was going to be sick, and she held onto the cards so tightly it hurt. The draft in the room dried her from the inside out and every breath she took hurt. Everything hurt. She felt like a spectator in her body, feeling it crumple and drop the cards on her lap. Feeling her father’s hand on her shoulder. He lightly thumped her on the back. When she coughed, it interrupted her paper bag lungs from opening and collapsing so quickly.

Sullivan kept a hand on her back while he put the student ids back, one by one. What she thought was her own was a girl she didn’t recognize. Kurotsuno could’ve cried right there for panicking over something so stupid.

**Notes for the Chapter:**

> THIS TOOK FOREVER. Also next chapter may also take a few days because I realized I've been completely neglecting my original work. Also also the tags are edited again hopefully for good this time, sorry for being such a scatterbrain lol


	4. Chapter 4

If there was one good thing Kurotsuno had to say about Mogeko Castle, it was that it had good internet. It was obvious why, if anyone bothered to look through the Mogekos’ browser history. Kurotsuno was online for a different reason, of course. Music filtered through her phone’s speakers and into the otherwise quiet hallway, and she hummed along while typing on the screen. Several feet ahead, Sullivan was checking each door. She had to roll her eyes at that; one bad room wouldn’t make her give up the condom search.

“Hanten says she wants us to drop by Maekami’s when we get home,” Kurotsuno told him without looking up. She could practically hear his grimace when he sighed, and she knew what that was all about. “Skip work and come drinking with us.”

“When you say things like that, I feel like a failure of a father,” Sullivan lamented, to which Kurotsuno furrowed her brow.

“You failed the first time you had sex with me.” Sullivan visibly wilted when she pointed that out, and turned back to the end of the hallway. “Also, you don’t need to check every door before we go through it. I’m not a little kid.”

She waited for some kind of retort, or even tears at being called out. She didn’t want to admit it, but she wanted a reaction. Anything that would show he was willing to be assertive. If he was going to fail her as a father, he might as well make it up to her by being a better lover—by her standards, of course.

Alas, there was nothing that could erase their familial bond. Kurotsuno knew this every time Sullivan looked at her with gentle concern. He was doing it now, right after checking what was behind the door at the end of the hall.

“Olivia…” Kurotsuno frowned when he used her name, but didn’t shrug him off when he put his hands on her shoulders. “I know you’re angry right now, but we must cooperate if we’re going to get out of here.”

Kurotsuno scowled in that way Sullivan often thought of as cute, but his reaction was strangely serious this time. “I need you to close your eyes for me. Can you do that?”

She was taken aback by this request, and questioned it, as she often did when receiving orders.

“You want to do ‘that’ now? Right here?”

“No, no.” Sullivan shook his head. “You don’t want to see what’s behind that door.”

“I think I can handle it.”

“You can’t.”

“I can.” Kurotsuno lightly kicked Sullivan’s leg, and was surprised once more when his grip on her shoulders tightened.

“Please. Just, for once, stop being difficult and trust me,” Sullivan demanded, brow furrowing. Kurotsuno, in spite of herself, felt her heart race. She swallowed and nodded slowly, feeling a bit cowed by his sudden dominance.

Sullivan took Kurotsuno’s earbuds out of her hands and put them into her ears. He must have known that she listened to her music loud. It wasn’t out of the question to assume she didn’t want to hear what was in the next room, either.

“Don’t take out your earbuds. And whatever you do, don’t let go of my hand.” Sullivan stood up, and then Kurotsuno’s vision went dark. It took her a moment to realize that he had just put a hand over her eyes, forcing them shut. She felt him adjust the volume on her phone, and then they were off.

Kurotsuno felt Sullivan put a hand on her shoulder and draw her against his side. With no way of seeing her phone, she kept a tight grip on it, not wanting to drop it. She didn’t get the impression that they’d be revisiting…wherever they were…after this.

Sullivan’s pace quickened, and he steered her to the right. Then left. She would’ve tripped if he didn’t have such a strong hold on her. If she concentrated on it, she could just barely feel his hands shaking. She did not make any move to comfort him, as she was having trouble balancing herself with her eyes covered. There was something about not having any sight that made her feel off-kilter.

She felt the ground ripple beneath her feet; she had stepped into something wet. Sullivan practically broke into a run seconds later, half-dragging her with him. The music flowed steadily into her ears, and its sound beating against her eardrums couldn’t distract her from how the air smelled.

Sullivan’s hand lifted from her eyes, and they were in a completely different hallway. Ahead was a large staircase. The way out? Kurotsuno removed her earbuds and put her phone into her bag, and then Sullivan’s arms were around her again.

Though he had been in contact with Kurotsuno for several minutes already, he was now clinging as though he had never been held in his life. As if she had almost died. As if she had died. Kurotsuno’s ears drooped when she heard his quiet sob. 

Ignorant as she was, she was having difficulty reconciling this crybaby with the man who had firmly told her to do what she was told.

**Notes for the Chapter:**

> Haha so reading this and the rest of my fic, I realized that it feels a little out of character...but it's not like we have to stick to canon when we write ^q^


	5. Chapter 5

The mansion deep in the woods had been lifeless for the duration of Sullivan and Kurotsuno’s trip, and its silence was only broken when the two of them trudged through the front door and kicked off their shoes. The place felt relatively untouched, like settled snow.

Kurotsuno had no reason to keep following Sullivan now that they were home, and went off by herself. In her room, in one of her desk drawers, were some personal effects she used for intimate encounters. Sure enough, there was an unopened box of condoms. Kurotsuno showered, and then took one with her to Sullivan’s room.

To her disappointment, the door was locked. If she pressed her ear against the wall, she could hear the faint rush of water. A shower, then. Some couples liked to intrude on their significant other while they were bathing, but Kurotsuno and her father were admittedly too shy to do that to each other. She decided instead to sit outside the door, and knock her horns against it when she heard the water stop.

Sullivan answered the door in a loose bathrobe and damp hair, and Kurotsuno held up the condom. He stared for a few moments, and then made a little ‘oh!’ in realization. For once, she couldn’t blame him for forgetting.

“Aren’t you tired?” Sullivan asked as Kurotsuno dropped onto his bed. She responded by making eye contact and holding out her arms. At that, he knelt over her and lifted up her nightshirt. With a flourish, he pulled it off her completely and tossed it to the floor. His own robe came next. Kurotsuno, already feeling wet between the legs, looked down to see that Sullivan’s dick was already standing at full mast.

There was little time to contemplate, as Sullivan had leaned down to start kissing her neck. Kurotsuno sighed into his hair and arched her back, silently inviting him to pay some attention to her chest, too. He did so, and Kurotsuno almost gasped when his tongue drags across her nipple. 

Sullivan lifted his head and gave Kurotsuno a look that she didn’t quite catch, because she had put her hands over her face. “What was that?”

When Kurotsuno did not answer, Sullivan put his mouth over her other nipple and started to suck. This drew more of a reaction out of her, one that Sullivan responded to with a low chuckle.

“Oliviaaaa. No need to be so shy.” Kurotsuno could practically hear the sly smile in his voice. She couldn’t decide if she hated or loved it. “Though I love that part of you, too.”

Sullivan gently moved Kurotsuno’s hands from her face so he could kiss her first on the lips, then her brow. His hands just as tenderly began to massage her chest. “Come on, now. Let Papa hear your voice.”

Kurotsuno shamefully obeyed with a soft whine, and this satisfied Sullivan enough to continue his journey down her body. He started all the way back at her neck and kissed back down to her chest, then her navel, until he was just above her pubic mound. Kurotsuno was growing impatient.

Sullivan, of course, wanted to take every opportunity to tease her. He spread her legs and kissed around her thighs, slowly moving inwards until she could feel his breath against her vulva.

Her vagina was already slick enough that Sullivan could’ve just started thrusting into her if he wanted. However, as was always the case with him, he liked taking things slow. He gave long tongue kisses to her labia, sucked on her clit and rubbed her thighs until she rocked her hips and orgasmed against his mouth.

She would’ve been ashamed at how long it took if she hadn’t been distracted by a rustling beside her. When she opened her eyes, she saw Sullivan licking his lips and holding the condom that she had brought with her. Just as he was tearing open the wrapper, however, she put her arm out to stop him.

“F…forget the condom,” she heaved, eyes glazed over with lust. “I, I want you to cum inside of me.”

Sullivan lit up in a way that made her wonder if he had been hoping she would say that. After all, he had wanted to do it when they were back in the castle. That felt like an eternity ago when the tip of his cock pressed against her labia.

They both moaned when he thrust his hips forward, sending his cock plunging into her. Even after many nights spent together, Kurotsuno had not quite gotten used to her father’s girth. Therefore, her moan was one of discomfort. Sullivan leaned over to embrace her, weaving his fingers through her hair as he began to hump her.

“You feel so good, Olivia,” he gasped between kisses. He hooked Kurotsuno’s arms over his elbows, and began to thrust with increasing intensity. “I just want to fill you to bursting. I love you, I love you—“

Kurotsuno, drifting between pleasure and pain, opened her mouth to cry out. The walls of her vagina contracted around Sullivan’s dick in a second orgasm, which left her mostly limp under his body. This didn’t stop him from pounding into her with reckless abandoned. There was nothing but their heavy breathing, the slapping of his hips against her, and the slight squelch with every other thrust.

Sullivan slammed down into Kurotsuno as hard as he could, and his dick throbbed and flooded her with hot cum. Her mewls only made him grind harder, his renewed energy making the mattress squeak. He unloaded once more into her before finally collapsing on top of her with a faint wheeze. 

He had expended more energy than he meant to, and it was finally catching up to him. Kurotsuno lay beneath him, panting and trying to roll onto her side. Sullivan let go of her legs and finally pulled out. It was like breaking a dam: cum flooded out of Kurotsuno’s vagina, drooling down her thighs and onto the sheets.

They both laid there in each other’s arms, exhausted but satisfied. They would clean up later, but for now, it was time to finally rest.

**Notes for the Chapter:**

> I'm finally done! I'll just stick to oneshots from now on.

**Author's Note:**

> So like I've sometimes thought about Kuro & Sulli being in Mogeko Castle together, so I decided to write a light-reading sort of fic where they just mess around. Since this is just for fun, I'm not going to take it /too/ seriously.


End file.
